Retrievable well packer

ABSTRACT

A well packer having an inner body carrying an initially retracted packing structure and a lower expander and associated slips expanded against a well casing by setting down on a tubing string attached to the inner body. An outer body surrounds and is spaced from the inner body to form a bypass passage therewith, the outer body carrying upper slips and an upper expander responsive to pressure in the bypass passage to shift the upper expander downwardly and expand the upper slips against the casing to anchor the packer against upward movement therein. The inner body and upper expander are attached to parts that coengage to prevent inadvertent downward shifting of the upper expander and expansion of the upper slips.

United States Patent lnventor Appl. No.

Filed Patented Assignee RETRIEVABLE WELL PACKER 14 Claims, 7 Drawing Figs.

u.s.cr. W ..a'zi 334 129 Field of Search References Cited UNITED STATES PATENTS 3/1959 Baker as a is &

3,020,959 2/1962 Nutter 7 3,399,729 9/1968 McGill 166/120 Primary Examiner Ernest R. Purser Attam'ey -Bernard Kriegel ABSTRACT: A well packer having an inner body carrying an initially retracted packing structure and a lower expander and associated slips expanded against a well casing by setting down on a tubing string attached to the inner body. An outer body surrounds and is spaced from the inner body toform a'bypass passage therewith, the outer body carrying upper slips and an upper expander responsive to pressure in the bypass passage to shift the upper expander downwardly and expand the upper slips against the casing to anchor the packer against upward movement therein. The inner body, and upper expander are attached to parts that coengage to prevent inadvertent downward shifting of the upper expander and expansion of the upper slips.

PATENTEU M22197! 3586; 106

sum 2 0F 2 laraea. 126.26.

iww/ RETRIEVABLE WELL PACKER The present invention relates to subsurface well bore equipment, and more particularly to subsurface well packers of the retrievable type.

Retrievable well packers are known and have been used for many years, which can be anchored against downward movement, as well as against upward movement. One such type of packer is illustrated in U.S. Pat. Re. No. 25,639. In general, it

is a well packer of the setdown type adapted to anchor the packer in a well casing against downward movement and to expand its packing structure outwardly against the wall of the well casing. The specific packer illustrated in this patent is anchored against upward movement by hydraulically expanding gripping elements, or anchor buttons, outwardly against the casing, the hydraulic pressure emanating from the exterior of the well tool below the packing element which flows to the hydraulic gripping elements or buttons through a bypass passage between an inner body or mandrel of the tool and an anchor body in which the gripping elements are shiftable radially into and from engagement with the well casing. The bypass passage is open during lowering or elevating of the well packer in the well casing. It is closed as a result of downward movement of the main body of the well packer in setting the packer against downward movement and expanding its packing structure against the well casing. The specific packer illustrated in U.S. Pat. Re. No. 25,639 also has a balancing piston responsive to the pressure of fluid in the bypass passage to exert a downward force on the inner body or mandrel, counteracting the pressure force tending to shift the body upwardly and, thereby, tending to open the bypass passage.

Well packers of the type illustrated in U.S. Pat. Re. No. 25,639 have operated very successfully. At times, however, the radially movable gripping elements or buttons do not retract readily when the well packer is to be released from the well casing, and it may become necessary to apply pressure externally of the well packer and above its packing elements to secure its retraction. However, such pressure cannot always be applied, as, for example, in wells which may have casing perforations above the setting location of the well packer. In addition, the imposition of a downward force on the well packer in setting its lower anchoring elements or slips and expanding the packing, may not place the tool in a coaxial position within the well casing, resulting in the tool being off center, which might result in an ineffeciive pack-off since the packer may be leaning toward one side of the casing.

By virtue of the present invention, an upper anchor is provided in a well packer of the general type illustrated in U.S. Pat. Re. No. 25,639 that overcomes the above-noted disadvantages. In lieu of the radially shiftable, hydraulically actuated anchor buttons or gripping elements, a downwardly tapering upper expander is used which is shifted downwardly hydraulically by fluid in the bypass passage to expand upper slips outwardly into anchoring engagement with the well casing, and thereby anchor the well packer against upward movement in the well casing. Such action effects a centering of the upper portion of the well packer and effectively centers the packing structure in the well casing, so that an effective packoff is assured. In addition, when the tool is to be retrieved, the upper expander is shiftable upwardly out of wedging relation to the upper slips by taking a positive mechanical upward pull on the tool, the upper slips be ing retracted positively from the well casing.

In general, the use of a downwardly tapering upper expander and associated upper slips in lieu of buttons in a setdown type of well packer has been suggested in U.S. Pat. No. 3,020,959. An illustration of the general arrangement also appears in U.S. Pat. No. 3,399,729, this latter patent deriving the hydraulic pressure for shifting the upper expander downwardly from a bypass passage. However, it possesses disadvantages in view of its relative complexity and the presence of a bypass passage of comparatively small cross-sectional area. In addition, the fluid actuatable area of the upper expander is limited so that a comparatively steep angle of taper for expanding and holding the slips outwardly is required.

With a well packer embodying applicants invention, the bypass around the tool has a large area. The pressure-actuatable area of the upper expander is also larger so that the angle of its tapered surface may, if desired, be made greater with respect to the axis of the well packer for the same outward wedging force imposed on the upper slips to retain them in gripping engagement with the wall of the well casing. In addition, applicants apparatus is more economical to manufacture and assemble, facilitating its reconditioning upon its retrieval from the well bore.

This invention possesses many other advantages, and has other purposes which may be made more clearly apparent from a consideration of a form in which it may be embodied. This form is shown in the drawings accompanying and forming part of the present specification. It will now be described in detail, for the purpose of illustrating the general principles of the invention; but it is to be understood that such detailed description is not to be taken in a limiting sense.

Referring to the drawings:

FIGS. la and lb together constitute a longitudinalsectional and side elevational view through a well packer embodying the invention, with its parts in retracted position for moving the tool longitudinally through a well casing, FIG. lb being a lower continuation of FIG. la;

FIGS. 2a and 2b together constitute a longitudinal sectional and side elevational view similar to FIGS. la and lb, illustrating the well packer anchored in packed-off condition against the well casing, FIG. 2b being a lower continuation of FIG. 2a;

FIG. 3 is a cross section taken along the line 3-3 on FIG. la;

FIG. 4 is a cross section taken along the line 4-4 on FIG. la;

FIG. 5 is a side elevational view of a portion of the releasable lock of the apparatus.

As illustrated in the drawings, a retrievable well packer A is provided, which is adapted to be anchored to a well casing B against movement in both upward and a downward directions, and to be packed off thereagainst to prevent leakage of fluid thereby. The lower portion C of the tool is a setdown type of.

well packer; whereas, its upper portion D is an anchor or holddown device for preventing upward movement of the tool in the well casing. The apparatus is lowered in the well casing on a tubular string E, such as tubing or drill pipe, extending to the top of the well bore and through which fluent substances under pressure, such as cement slurry, acid, and the like, can be pumped through a passage 10 of the tool and discharged from its lower portion.

The well packer includes a central main body or inner mandrel 11 having the passage 10 therethrough that may be of relatively large diameter, and preferably no smaller than the diameter through the tubular string E thereabove. The upper portion of this body is threadedly secured to a coupling 12 which is, in turn, threadedly attached to the lower end of the tubular string. The inner body extends downwardly through substantially the entire length of the tool and has a threaded pin 13 secured to a body sub 14 having a lower threaded pin 15 for securing the tool to a lower tool or lower section of tubing (not shown).

The upper portion D of the tool includes an anchor body 16, made of several interconnected sections, which surrounds the inner body 1 l in spaced relation thereto and which is relatively slidable with respect thereto. The spaced relation between the inner and outer bodies provides a portion of an annular bypass passage 17 therebetween, described hereinbelow. This body 16 includes an upper valve member 18 adapted to engage an elastomer valve seat 19 secured to the inner body for the purpose of closing the upper end of the bypass passage 17. The elastomer valve seat bears against the lower end of a retainer ring 20 encompassing a split ring 21 mounted in an external groove 22 in the inner body I], a stop ring 23 surinwardly directed lower flange 25 on the retainer sleeve for holding the elastomer valve seat assembled to the inner body 11. The outer body 16 further includes a pressure-balancing cylinder section 26 having its upper head portion 27, threadedly secured to the valve member 18 and its lower sleeve 28 threadedly secured to the skirt 29 ofa piston 30, the annular pistonhead 31 of which is integral with a depending outer body portion 32, the lower end of which is threadedly secured to a slip ring 33 which is, in turn, threadedly attached to the support sleeve 34 of a packing structure 35.

The slip ring 33 carries a plurality of circumferentially spaced upper slips 36 slidable transversely of the slip ring, but movable longitudinally with the slip ring, by virtue of lower inverted T-shaped heads 37 on the slips slidable within companion T-shaped radial slots 38 in the upper portion of the slip ring. The upper portions 39 of the slips have upwardly facing wickers or teeth 40 for anchoring engagement in the wall of the well casing in which the packer is used, these slips being expandable outwardly upon downward movement of an upper expander 41 along the outer body section 32, the upper expander having circumferentially spaced grooves 42 therein receiving the upper portions of the slips, the base 43 of each groove being tapered in a downward and inward direction and engaging companion inclined or tapered surfaces 44 on the rear portions of the slips. The slips are retractable from their expanded condition as a result of moving the upper expander 41 upwardly, the upper expander having inclined grooves 45 in opposite sides of its slots receiving companion inclined tongues 46 on the slips, and thereby providing a positive slidable connection between the upper expander and the upper slips. Upward movement of the upper expander 41 relative to the slips 36, when the latter are in their expanded condition, will cause the outer sides of the expander grooves 45 to engage the slip tongues 46 and shift the slips positively radially inwardly to their initial retracted position.

The upper portion 47 of the upper expander forms an annular cylinder head of a hydraulic cylinder 48 which surrounds the piston portion 30 of the body 16. A cylinder sleeve 49 is threadedly secured to the upper expander and extends upwardly therefrom, this cylinder sleeve being integral with an upper holding sleeve portion 50 which extends upwardly to a position above the stop ring 23, where it terminates in an inner inwardly directed stop flange 51 overlying the stop ring to be engaged thereby. Above the cylinder sleeve 49, the holding sleeve 50 may be provided with a plurality of elongate, circumferentially spaced slots 52 extending through its wall.

The outer body immediately below its annular piston head 31 has one or a plurality of ports 53 therethrough establishing communication between the bypass passage 17 and the annular cylinder space 54 provided between the piston 31 and cylinder head 47, such that fluid under pressure in the bypass passage can enter the cylinder space for the purpose of shifting the upper expander 41 downwardly along the body 16 and with respect to the upper slips 36 to expand the latter outwardly against the well casing B.

Fluid under pressure below the well packer tends to elevate the inner body 11 and may, therefore, inadvertently open the bypass passage 17 by removing the valve seat 19 from the valve head 18 when the tool is anchored in packed-off condition in the well casing To counteract this undesired result, an annular balancing piston 55 is disposed within the upper cylinder 26, including an upper piston head 56 slidable along the inner wall of the cylinder and having a skirt 57 slidable along the upper inner portion 58 of the outer piston 30. The lower end of the balancing piston skirt 57 is engageable with an upwardly facing thrust shoulder 59 on an external flange 60 secured to the inner body or mandrel ll of the too], this flange being longitudinally slotted so as to permit fluid to flow from within the outer piston 30 along the interior of the upper piston skirt 57 and through the annular passage 17 between the valve member 18 and the inner body 11, for continued upward passage through the tubing-casing annulus N above the tool. The balancing piston 55 has a suitable side seal ring 61 mounted in its head for slidable sealing along the inner wall of the upper cylinder skirt 28, the upper portion 58 of the piston 30 also having an internal seal 62 along which the balancing piston skirt 57 is slidable. The annular space 63 in the upper cylinder 26 between the piston skirt 57 and the cylinder skirt 28 communicates through a lower bleeder passage 64 in the cylinder skirt with the exterior of the tool, so that pressure in the bypass passage 17 can act in a downward direction over the area R of the balancing piston 55 and urge it downwardly in its cylinder, bringing it to bear against the thrust shoulder 59 and exert a downward hydraulic thrust on the inner body member 11.

The fluid under pressure in the bypass passage 17 can also pass into the expander cylinder space 54 and tend to shift the upper expander 41 downwardly within the upper slips 36 to expand the latter outwardly. This fluid under pressure acts over the annular area S of the cylinder head 47 between the periphery of the outer body portion 32 below the piston 31 and the inner wall of the cylinder sleeve 49. Fluid leakage from the cylinder space 54 is prevented by a side seal 66 on the piston 31 engaging the sleeve 49 and a side seal 67 on the cylinder head 47 engaging the outer body portion 32.

The upwardly anchoring portion D of the well packer is secured to the downwardly anchoring portion C of the well packer. The packing structure 35 for effecting a seal against the wall of the well casing B includes an upper gauge ring 70 threadedly attached to the upper slip ring 33 and providing an upper abutment for the packing structure, this packing structure also including the support sleeve 34 previously referred to, which is in spaced relation to the inner body 11 of the well packer, this support sleeve being slidable relative to the inner body or mandrel and extending through the packing elements of the packing structure 35, which may be of any suitable type. As shown, the packing structure includes an upper rubber or rubberlike packing element 71 engaging the lower end of the upper gauge ring 70 and also engaging a metallic spacer ring 72, which, in turn, contacts an intermediate rubberlike packing element 73, the lower end of which engages a metallic spacer ring 74 which contacts the upper end of a rubber or rubberlike packing element 75 that engages a lower abutment or gauge ring 76 threadedly attached to a lower expander 77. This lower abutment 76 has an inwardly directed flange or a downwardly facing shoulder 78 adapted to contact an outwardly extending flange 79 at the lower end of the support sleeve 34.

When the upper abutment 70 is moved toward the lower abutment 76, the packing members 71, 73, 75 are shortened and expanded outwardly into sealing engagement with the wall of the well casing B, as well as against the periphery of the support sleeve 34. When the upper abutment 70 moves toward the lower abutment 76, the lower end of the support sleeve shift downwardly in an annular space 80 between the lower expander and the periphery of the mandrel 11. The lower expander is of generally frustoconical shape and is adapted to coact with a plurality of circumferentially spaced lower slips 81 for anchoring the apparatus against downward movement in the well casing. When the packing structure 35 is in retracted position, the lower abutment 76, as stated above, engages the external lower flange 79 on the support sleeve 34.

Fluid can pass through the space surrounding the lower portion of the well packer and the lower expander 77, flowing inwardly through a plurality of circumferentially spaced ports or openings 82 in the sleeve portion of the expander to its interior 80, and then flowing upwardly through the annular bypass passage 83 between the support sleeve 34 and body 11, and through the annular bypass passage 17 thereabove, discharging through and around the upper end of the valve head 18 into the annulus N surrounding the tool and the tubular string E thereabove. When the tubular string E and inner body 11 are lowered relative to the members surrounding the inner body, the valve seat 19 secured to the inner body is moved downwardly into engagement with the upper end of the valve head 18, closing the bypass passage 17, 83, B0, 82.

A connector sleeve 84 is slidably mounted on the exterior of the inner body 11 of the tool, its upper portion extending within the lower expander 77. The connector sleeve terminates in an upper stop member or nut 85 threadedly secured thereto that projects outwardly and is adapted to engage an upwardly facing shoulder 86 on the lower expander. The lower end of the connector sleeve has an external flange 87 received within a recess 88 in the body sub 14 and disposed under an internal flange 89 ofa control sleeve 90 surrounding the body sub 14. This control sleeve is threadedly secured to a slip sleeve 91 surrounding the connector sleeve 84 which has a plurality of longitudinally extending, circumferentially spaced grooves 92 in which the lower slips 81 are laterally movable. These slips each include a lower drag portion 93 adapted to frictionally engage the inner wall of the well casing, being urged outwardly thereagainst by one or a plurality of compression springs 94 engaging the bases of the grooves 92 and the drag portions of the slips. The slips 82 include upper anchor portions 95 having downwardly facing wickers or teeth 96 adapted to engage and embed themselves in the wall of the well casing to prevent downward movement of the slips therealong when expanded outwardly by the lower expander 77.

The lower expander 77 has a downwardly and inwardly inclined tapered surface 97 adapted to coact with companion inner tapered surfaces 98 on the anchor portions 95 of the slips. Outward expansion of the slips 81 under the influence of the springs 94 is limited by a retainer ring 99 encompassing the central portions of the slips and received within external grooves 100 therewithin. Outward movement is also limited by engagement of lower terminals 101 of the slips below their drag portions 93 with an upper rim 102 of the control sleeve 90.

The control sleeve forms part of a lock device releasably connecting the control sleeve to the bottom body sub 14. The lock device controls relative longitudinal movement between the inner body 11 and the parts surrounding it. When in locked condition, the well packer parts move as a unit longitudinally in the well casing with the upper and lower slips 36, 81 and the packing structure 35 in retracted position. When the control sleeve and lower slips 81 are in the lower position, as illustrated in FIG. 1b, the flange 89 on the control sleeve engages the lower flange 87 on the connector sleeve to prevent relative upward movement of the connector sleeve with respect to the inner body or mandrel 11, at which time the upper nut 85 on the connector sleeve is engaging the upwardly facing shoulder 86 of the lower expander member 77. However, when the controlsleeve 90 is out of locking relation to the body sub 14, the inner body 11 can move downwardly relative to the control sleeve, as described hereinbelow.

The lower slips 81 are prevented from having substantial longitudinal movement relative to the slip sleeve 91 by their engagement with the retainer ring 99, and by virtue of the fact that the retainer ring also engages an upper external flange 105 of the slip sleeve. When the slip sleeve 91 is moved downwardly, its upper flange 105 engages the retainer ring 99 which engages the lower sides of the slip grooves 100 to pull the slips 81 downwardly in the well casing. When the slip sleeve 91 and the control member 90 are moved upwardly, the bottoms 106 of the slip sleeve grooves 92 engage the lower ends 101 of the slips to shift them upwardly along the wall of the casing. The slips 81 themselves are of the rocker type, in that the anchor portions 95 are removed from engagement with the wall of the well casing when the springs 94 are permitted to force the drag portions 93 into full contact with the wall of the casing. However, when the expander 77 moves downwardly within and behind the anchor portions 95 of the slips, the latter will rock outwardly about the upper ends of the drag portions 93, which fulcrum on the casing to effect shifting of the anchor portions outwardly against the well casing and embed their teeth 96 therewithin.

The releasable lock portion of the apparatus includes the control sleeve 90 which has a plurality, such as a pair, of J- slots 110 therein, the longitudinal legs 111 of which terminate in lower hook portions 112 on the control sleeve. Received in these slots are radially extending J-pins 113 integral with the body sub, which can occupy a locked position above the hooks 112, but which can be turned with the body sub 14 in a clockwise direction out of its location above the hook portions of the .l-slots for movement downwardly through the openings 114 between the hooks and opposed sloping sides 115 of the sleeve that open downwardly through the sleeve, to permit the pins 113 to move to a position below the sleeve in response to downward movement of the inner body 11 and the bottom sub 14 attached thereto, thereby completely releasing the inner body 11 from the control sleeve and permitting the body to shift downwardly. Upward movement of the inner body 11 relative to the control sleeve 90 will cause the pins 113 to engage the tapering sides 115, which will automatically turn the body in a counterclockwise direction and place the pins 113 back into a locking relation within the slots 110 of the sleeve above the hook portions 112, to reconnect the body 11 to the control sleeve 90.

In the use of the apparatus within the well casing, its parts occupy an initially retracted position, as disclosed in FIGS. 1a and lb, in which the J-pins 113 are disposed in the .l-slots 110 above the hook portions 112, at which time the stop ring 23 on the inner body member 11 is engaging the stop flange 51 on the upper expander extension sleeve 50 to retain the expander 41 in its upper position in engagement with the piston 30, which will hold the support sleeve 34 in its upper position, with its flange 79 engaging the lower gauge ring or abutment 76, which retains the lower expander 77 in its elevated position above the anchor portions of the lower slips 81, At this time, the upper end of the bypass passage 17 is open, since the valve seat 19 is disposed longitudinally above the upper end of the valve head 18. As the well packer A is lowered in the well casing, the drag portions 93 of the slips8l tend to resist their downward movement in the casing B, as well as downward movement of the slip sleeve 91 and the control sleeve 90. The inner body 11 then shifts downwardly a short distance until the .l-pins 113 engage the hooks 112 of the sleeve causing the control sleeve 90 to be pulled downwardly with the inner body. The control sleeve flange 89 then engages the flange 87 of the connector sleeve 84, which, through engagement of its upper nut 85 with the lower expander 77, exerts a downward pull on the lower expander, which acts through the lower abutment 76 to exert a downward pull on the support sleeve 34, the upper slip ring 33, and the outer body structure 16. The T-slot connection 37, 38 of the ring 33 with the upper slips 36 causes the latter also to be moved downwardly in response to downward movement of the inner body, the outer body piston 30 engaging the cylinder head 47 of the upper expander 41 to pull the latter downwardly. Thus, all parts move as a unit, with the slips 36, 95 in retracted position and with the packing structure 35 in its retracted position.

When the setting location is reached in the well casing B, the tubular string E is elevated a slight distance to move the J pins 113 above the hooks 112, and the tubing string then turned to the right while it is lowered, which will shift the pins 113 out of the control sleeve 90. The inner body 11 moves downwardly until its valve seat 19 engages the valve head 18 to close the valve passage 17, whereupon the downward movement is transmitted through the outer body 16 to the upper slip ring 33 and upper abutment 70, and from the latter through the packing structure 71 to 76 to the lower expander 77. The lower expander shifts downwardly behind the lower slips 81, since downward movement of the latter is resisted by the fractional engagement of the drag portions 93 against the wall of the well casing, rocking the anchor portions 95 of the slips outwardly and wedging them against the well casing, which then precludes further downward movement of the lower expander 77 and the lower abutment 76. Continued downward movement of the inner body member 11 then shifts the upper abutment 70 toward the lower abutment 76 to shorten the packing elements 71, 73, 75 and expand them into firm sealing engagement with the wall of the well casing B and with the periphery of the support sleeve 34, the lower flange 79 of the support sleeve shifting downwardly away from the companion inwardly directed flange 78 of the lower gauge ring 76, as disclosed in FIG. 2b. With the parts in this condition, the stop ring 23 has moved away from the stop flange 51 of the holding sleeve 50, which is attached to the upper expander 41, permitting subsequent downward movement of the upper expander when the upper slips 36 are to be expanded against the casing.

Fluid under pressure can now be forced down through the tubular string E and the inner body 11, discharging from the lower end of the body sub 14, such fluid under pressure then being imposed on the fluid surrounding the lower portion of the tool and passing in through the expander ports 82 into the annular bypass passage 83, 17 between the support sleeve 34 and outer body 16, on the one hand, and the inner body 11, on the other hand. Such fluid under pressure can act in a downward direction on the balanced piston 55 to engage its lower end with the thrust shoulder 59 on the body flange 60 to counteract the upward hydraulic force imposed on the inner body 11 and tending to shift it upwardly. The effective pressure actuatable area R of this piston may be made slightly greater than the effective cross-sectional area of the inner body member 11, so that there is a net fluid pressure force urging and holding the inner body in a downward position, to retain the valve seat 19 sealingly engaged with the valve head 18 and the bypass passage 17 in its closed condition. The fluid under pressure is also exerted through the inlet ports 53 in the fluid in the cylinder space 54 between the piston 30 and head 47 on the upper expander, shifting the upper expander 41 downwardly along the upper slips 36 and expanding the latter outwardly into firm anchoring engagement with the wall of the well casing.

The greater the pressure in the tool and within the bypass 17, the greater will be the downward hydraulic force on the upper expander 41 holding it wedged behind the slips and retaining their wickers 40 anchored against the well casing. Such anchoring of the upper slips against the well casing will prevent hydraulic forces acting upwardly on the tool from shifting it in an upward direction, and will retain the tool anchored in packed-off condition against movement in both longitudinal directions in the well casing, as illustrated in FlGS. 2a and 2b.

When the tool is to be released, an upward pull is taken on the tubular string 13 and the'inner body member 11, which will shift the valve seat 19 upwardly away from the valve head 18 to open the bypass 17, 83 and equalize the pressure above and below the packing structure 35. The inner body member 11 moves upwardly until its stop ring 23 engages the stop flange 51 of the holding sleeve 50, which will then pull the upper expander 41 upwardly and retract the upper slips 36 from the well casing, because of the slidable, inclined tongue and groove interconnection 45, 46 between the expander and the upper slips. Upward movement of the upper expander 41 along the outer body member 16 continues until the expander head 47 engages the piston 30, which then exerts an upward pull on the upper slip ring 33 and the upper abutment 70 to elevate the latter in a direction away from the lower abutment 76, removing the compression force on the packing elements 71, 73, 75 and allowing them to inherently shift inwardly to their initial retracted position. Continued upward movement of the inner body member 1 1 and of the upper anchor portion D of the tool surrounding it, as well as the retracted packing structure 35, then causes the lower flange 79 on the support sleeve to exert an upward pull on the lower abutment 76 and the lower expander 77, elevating the latter with respect to the lower slips 8], permitting the springs 94 to rock the drag portions 93 of the slips into full surface engagement with the well casing and shift the anchor portions 95 of the slips inwardly out of engagement with the well casing. When this occurs, the .l-pins 113 have moved back into the control sleeve 90. The tubular string E and the inner body 11 can then be turned a short distance to the left to be assured that the control pins are again disposed above and in alignment with the hook portions 112 of the control sleeve. In fact, upward movement of the body 11 will cause the pins 113 to slide along the inclined surfaces 115 of the control sleeve and be automatically positioned in a locking relation to the control sleeve.

Upward movement of the well packer can now continue, the parts occupying the relative positions illustrated in FIGS. 1a and 1b. The inner body member 11 is acting through the stop ring 23 to exert an upward pull on the holding sleeve 50 and retain the upper expander 41 in its upper position, thereby holding the upper slips 36 in their retracted position. During upward movement of the tool, the lower expander 77 is being held upwardly out of wedging relation to the anchor portions of the slips 81. As a result, the well packer A can be elevated to the top of the well bore and removed entirely therefrom. During such upward movement, the fluid in the annular space N around the tubular string can bypass the interior of the packing structure by flowing inwardly through the bypass 17, 83. It can also bypass the exterior of the retracted packing structure 35.

During elevating movement of the packer in the well casing, inadvertent downward movement of the upper expander 41 cannot occur to expand the upper slips 36 outwardly against the casing. During downward movement of the tool through the well casing, the upper expander 41 cannot shift downwardly of the upper slips, nor can the lower expander 77 move downwardly within the lower slips 81, in view of the coengagement of the outer body 16 with the upper expander 41 and of the support sleeve 34 connected thereto with the lower abutment 76 secured to the lower expander. Thus, the parts cannot move from their retracted positions during both upward or downward movement through the well casing, despite the fact that fluid pressure might build up in the annular passage 17, 83, tending to shift the upper expander downwardly within the upper slips.

Because of the specific structural arrangement between the parts of applicants anchor portion, a relatively large annular bypass passage area is provided to assure large volume flow through the bypass 17, 83. In addition, the provision of the annular cylinder 48 surrounding the annular piston 30 and which is secured to the upper expander 41, allows the effective crosssectional areas of the cylinder head 47 on which fluid pressure acts to be made larger than prior devices. Accordingly, for the same unit pressure, a larger downward force can be imposed on the upper expander 41 to hold the upper slips 36 anchored against the well casing. In view of the availability of such larger downward force, the taper angle to the vertical of the coengaging expander and slip surfaces 43, 44 can be made greater, with assurance that the upper slips 41 will remain anchored against the well casing B. Assurance is also had that the slips 36 can be retracted since the wedge angle of the tapered surfaces 43, 44 is less.

lclaim:

1. In a well packer adapted to be lowered in a conduit disposed in a bore hole on a running-in string: a tubular inner body connectable to the running-in string; an outer body surrounding and spaced laterally from said inner body to form a substantially circumferentially continuous annular passage therebetween; packing means around said outer body for sealing with the conduit; said annular passage extending from locations above and below said packing means; slip means movable between retracted and expanded positions for anchoring said outer body to the conduit against movement in both longitudinal directions; hydraulically operable means responsive to fluid pressure in said passage for expanding at least part of said slip means against the conduit; and coengageable means on said inner body and hydraulically operable means for releasably retaining said part of said slip means in retracted position.

2. In a packer as defined in claim 1', and means on said inner and outer bodies selectively engageable and disengageable with each other for opening and closing said passage.

3. ln a packer as defined in claim I; said coengageable means including means secured to said hydraulically operable means and extending upwardly therefrom around said outer body to a location thereabove, said coengageable means further including stop means on said inner body engageable with said means secured to said hydraulically operable means.

4. ln a packer as defined in claim 1; said part of said slip means including slips, an expander above said slips and movable downwardly thereof to expand said slips against the conduit; said hydraulically operable means including cylinder and piston means connected to said expander; said coengageable means of said hydraulically operable means being securcd to said cylinder and piston means.

5. ln a packer as defined in claim 1; said part of said slip means including slips, an expander above said slips and movable downwardly thereof to expand said slips against the conduit; said hydraulically operable means including a piston secured to said outer body and a cylinder slidable along said piston and secured to said expander; said coengageable means of said hydraulically operable means being secured to said' cylinder.

6. in a packer as defined in claim 1; said part of said slip means including slips, an expander above said slips and movable downwardly thereof to expand said slips against the conduit; said hydraulically operable means including a piston secured to said outer body and a cylinder slidable along said piston and secured to said expander; said coengageable means of said hydraulically operable means being secured to said cylinder and extending upwardly therefrom around said outer body to a location thereabove, said coengageable means including stop means on said inner body above said outer body and engageable with said coengageable means of said hydraulically operable means secured to said cylinder.

7. In a packer adapted to be lowered in a conduit disposed in a bore hole on a running-in string: a tubular inner body connectable to the running-in string; an outer body surrounding said inner body and providing a passage therebetween; an annular piston secured to said outer body; an annular cylinder surrounding said piston and outer body; an expander below and secured to said cylinder; slips below and engageable with said expander; means for conducting fluid under pressure from said passage to said cylinder to shift said cylinder downwardly along said piston and said expander downwardly along said slips to expand said slips against the conduit; holding means secured to said cylinder and extending upwardly therefrom to a location above said outer body; and stop means on said inner body engageable with said holding means to retain said expander in an upper position out of expanding relation to said slips.

8. In a packer as defined in claim 7; and coengageable valve means on said bodies for selectively opening and closing said passage above said conducting means.

9. In a packer as defined in claim 7; said bodies being laterally spaced from each other whereby said passage is circumferentially continuous.

10. In a packer as defined in claim 7; said bodies being laterally spaced from each other whereby said passage is circumferentially continuous; and coengageable first and second valve means on said bodies for selectively opening and closing said passage substantially at the upper end of said outer body.

1]. In a packer as defined in claim 7; said bodies being laterally spaced from each other whereby said passage is circumferentially continuous; and coengageable first and second valve means on said bodies for selectively opening and closing said passage substantially at the upper end of said outer body; said stop means and first valve means being fixed to said inner body; and said second valve means being fixed to said outer body.

12. In a well packer adapted to be lowered in a conduit disposed in a bore hole on a running-in string: a tubular inner body connectable to the running-in string; an outer body surrounding and spaced laterally from said inner body to form a substantially continuous annular passa e therebetween; packing means surrounding said outer bo y for sealing with the well conduit; a lower expander below and secured to said packing means; lower slips below and expandable by said lower expander into engagement with the conduit; means releasably connecting said lower slips to said inner body; upper slips on said outer body above said packing means; an upper expander externally of and slidable downwardly along said outer body to expand said upper slips against the conduit; said outer body having an annular piston thereon; an annular cylinder secured to said expander and extending upwardly therefrom in slidable sealing relation to said piston; means for conducting fluid under pressure from said passage into said cylinder to shift said cylinder downwardly and said upper expander downwardly along said upper slips; holding means secured to said cylinder and extending upwardly along said outer body and terminating above said outer body; and stop means on said inner body movable upwardly therewith into engagement with said holding means above said outer body to prevent downward shifting of said upper expander along said upper slips.

13. In a packer as defined in claim 12; and coengageable first and second valve means on said bodies for closing said passage above said conducting means.

14. In a packer as defined in claim 12; said inner body being movable downwardly into engagement with said outer body to shift said lower expander downwardly along said lower slips and expand said lower slips against the casing; coengageable first valve means on said inner body engageable with said second valve means on said outer body upon downward movement of said inner body within said outer body to close said passage; said stop means being secured to said inner body and being movable upwardly therewith into engagement with said holding means after said first valve means has been disengaged from said second valve means upon such upward movement of said inner body. 

1. In a well packer adapted to be lowered in a conduit disposed in a bore hole on a running-in string: a tubular inner body connectable to the running-in string; an outer body surrounding and spaced laterally from said inner body to form a substantially circumferentially continuous annular passage therebetween; packing means around said outer body for sealing with the conduit; said annular passage extending from locations above and below said packing means; slip means movable between retracted and expanded positions for anchoring said outer body to the conduit against movement in both longitudinal directions; hydraulically operable means responsive to fluid pressure in said passage for expanding at least part of said slip means against the conduit; and coengageable means on said inner body and hydraulically operable means for releasably retaining said part of said slip means in retracted position.
 2. In a packer as defined in claim 1; and means on said inner and outer bodies selectively engageable and disengageable with each other for opening and closing said passage.
 3. In a packer as defined in claim 1; said coengageable means including means secured to said hydraulically operable means and extending upwardly therefrom around said outer body to a location thereabove, said coengageable means further including stop means on said inner body engageable with said means secured to said hydraulically operable means.
 4. In a packer as defined in claim 1; said part of said slip means incluDing slips, an expander above said slips and movable downwardly thereof to expand said slips against the conduit; said hydraulically operable means including cylinder and piston means connected to said expander; said coengageable means of said hydraulically operable means being secured to said cylinder and piston means.
 5. In a packer as defined in claim 1; said part of said slip means including slips, an expander above said slips and movable downwardly thereof to expand said slips against the conduit; said hydraulically operable means including a piston secured to said outer body and a cylinder slidable along said piston and secured to said expander; said coengageable means of said hydraulically operable means being secured to said cylinder.
 6. In a packer as defined in claim 1; said part of said slip means including slips, an expander above said slips and movable downwardly thereof to expand said slips against the conduit; said hydraulically operable means including a piston secured to said outer body and a cylinder slidable along said piston and secured to said expander; said coengageable means of said hydraulically operable means being secured to said cylinder and extending upwardly therefrom around said outer body to a location thereabove, said coengageable means including stop means on said inner body above said outer body and engageable with said coengageable means of said hydraulically operable means secured to said cylinder.
 7. In a packer adapted to be lowered in a conduit disposed in a bore hole on a running-in string: a tubular inner body connectable to the running-in string; an outer body surrounding said inner body and providing a passage therebetween; an annular piston secured to said outer body; an annular cylinder surrounding said piston and outer body; an expander below and secured to said cylinder; slips below and engageable with said expander; means for conducting fluid under pressure from said passage to said cylinder to shift said cylinder downwardly along said piston and said expander downwardly along said slips to expand said slips against the conduit; holding means secured to said cylinder and extending upwardly therefrom to a location above said outer body; and stop means on said inner body engageable with said holding means to retain said expander in an upper position out of expanding relation to said slips.
 8. In a packer as defined in claim 7; and coengageable valve means on said bodies for selectively opening and closing said passage above said conducting means.
 9. In a packer as defined in claim 7; said bodies being laterally spaced from each other whereby said passage is circumferentially continuous.
 10. In a packer as defined in claim 7; said bodies being laterally spaced from each other whereby said passage is circumferentially continuous; and coengageable first and second valve means on said bodies for selectively opening and closing said passage substantially at the upper end of said outer body.
 11. In a packer as defined in claim 7; said bodies being laterally spaced from each other whereby said passage is circumferentially continuous; and coengageable first and second valve means on said bodies for selectively opening and closing said passage substantially at the upper end of said outer body; said stop means and first valve means being fixed to said inner body; and said second valve means being fixed to said outer body.
 12. In a well packer adapted to be lowered in a conduit disposed in a bore hole on a running-in string: a tubular inner body connectable to the running-in string; an outer body surrounding and spaced laterally from said inner body to form a substantially continuous annular passage therebetween; packing means surrounding said outer body for sealing with the well conduit; a lower expander below and secured to said packing means; lower slips below and expandable by said lower expander into engagement with the conduit; means releasably connecting said lower slips to said inner body; upper slips on said outer body above said packing means; an upper expander externally of and slidable downwardly along said outer body to expand said upper slips against the conduit; said outer body having an annular piston thereon; an annular cylinder secured to said expander and extending upwardly therefrom in slidable sealing relation to said piston; means for conducting fluid under pressure from said passage into said cylinder to shift said cylinder downwardly and said upper expander downwardly along said upper slips; holding means secured to said cylinder and extending upwardly along said outer body and terminating above said outer body; and stop means on said inner body movable upwardly therewith into engagement with said holding means above said outer body to prevent downward shifting of said upper expander along said upper slips.
 13. In a packer as defined in claim 12; and coengageable first and second valve means on said bodies for closing said passage above said conducting means.
 14. In a packer as defined in claim 12; said inner body being movable downwardly into engagement with said outer body to shift said lower expander downwardly along said lower slips and expand said lower slips against the casing; coengageable first valve means on said inner body engageable with said second valve means on said outer body upon downward movement of said inner body within said outer body to close said passage; said stop means being secured to said inner body and being movable upwardly therewith into engagement with said holding means after said first valve means has been disengaged from said second valve means upon such upward movement of said inner body. 